1. Field of the Invention
The present invention relates to an automatic changer and, more particularly, to an automatic changer that selects one cartridge-type recording medium from among a large number of such recording media accommodated in a recording/reproducing apparatus, and moves this selected recording medium to a desired position.
2. Description of the Related Art
Conventionally, there has been practically used an automatic changer for cartridge-type recording media which is structured to accommodate a plurality of double-reel type audio or video cassette tapes or single-reel type data recording cartridge tapes on shelves within one accommodation box. The automatic changer selects one desired tape from among these tapes, and conveys this tape to a reproducing or recording apparatus.
This automatic changer is used being connected to a computer system such as a server, personal computer, and so on. In this automatic changer, a plurality of cartridges are accommodated on shelves, and a hand mechanism section is provided on an accessor that is movably structured to hold and convey a cartridge. A bar code label is adhered to a surface of each cartridge at the hand mechanism section side.
On the other hand, a bar code reader is provided on a base section of the hand mechanism section adjacent to the hand mechanism section. This bar-code reader reads the bar code label adhered to each cartridge, and identifies this cartridge. The conventional library device uses a laser bar-code reader. This bar-code reader irradiates laser beams onto the cartridge over a predetermined range of this cartridge, and reads the bar code.
Japanese Patent Application Laid-open Publication No. 5-144147 discloses an automatic changer that is an improved conveyor of an automatic cassette changer for a television broadcasting station that is used to reproduce or edit the recording of a series of videos over many hours while changing a plurality of video cassettes. According to this automatic changer, a bar-code reader provided on the hand mechanism section of this automatic changer can directly and continuously read bar codes provided on the side surfaces of cassettes, in order to specify a plurality of cassettes accommodated on a plurality of shelves.
Further, according to the automatic changer disclosed in Japanese Patent Application Laid-open Publication No. 5-144147, a hand block selectively holds one of the plurality of cassettes accommodated on the plurality of accommodation shelves, and conveys this selected cassette to a recording/reproducing apparatus. A label printed with a bar code is adhered to the hand-block side end surface of each cassette accommodated on each accommodation shelf.
The hand block is fitted to the conveyor via an arm, to move freely between the accommodation shelf and the recording/reproducing apparatus to convey one cassette. For this purpose, four cassette-holding pins are provided on the hand block to hold one cassette. On the side surface of the hand block, a bar-code reader is adhered to scan and read bar codes of the plurality of cassettes.
Further, according to the automatic changer disclosed in Japanese Patent Application Laid-open Publication No. 5-144147, the hand block moves the bar-code reader along the bar codes of the plurality of cassettes that are accommodated on the plurality of accommodation shelves. The bar-code reader sequentially and continuously reads these bar codes, and identifies each cassette.
However, in recent years, an apparatus that utilizes a CCD (charged-coupled device) has come to be practically used as an image pick-up member, instead of using laser beams to read bar codes. According to this apparatus that utilizes the CCD, the CCD reads an image of a bar code, analyzes this image, and reads the contents of the bar code. In order for the CCD to read the bar code, it is necessary to provide a condenser lens that focuses the image of the bar code on the CCD.
However, as the bar-code reader of the library device is a large laser type, and is mounted adjacent to the hand mechanism section, the movable range of the hand mechanism section becomes small. Therefore, the space in which the cartridges are accommodated has become narrow. Further, there is a range of distance over which the bar-code reader can read bar codes. Therefore, there has been a risk that the bar-code reader cannot read bar codes when the distance between the bar-code reader and the bar code labels changes.
Further, according to the automatic changer disclosed in Japanese Patent Application Laid-open Publication No. 5-144147, the bar-code reader is mounted on the side surface of the hand mechanism section. Therefore, there has been a problem that the hand mechanism section is large, and a wasteful space is generated in the apparatus. When a reflection-type sensor or a laser-type sensor is mounted on the bar-code reader, there is margin in the reading distance from the bar-code reader to the bar code labels. However, these types of sensors are very expensive, and the mounting of these devices leads to a high cost of the bar-code reader.
On the other hand, when a CCD is used to read the bar codes, it is possible to minimize the cost of the bar-code reader, as the CCD is at a very low cost (ten percent of the cost of the laser type). However, this has had a problem that there is no margin in the reading distance. In order to solve this problem, a condenser lens is fitted to a holding mechanism of the hand mechanism section that moves forward and backward. By controlling the lens position (that is, by automatically focusing the image of the bar code), the distance margin for the reading is increased. However, as the CCD and the condenser lens are also mounted in this case, a large space is necessary for their accommodation. Therefore, the hand mechanism section is large, and this limits the moving area of the hand mechanism section. Consequently, there has been a problem that only a small number of cartridges can be accommodated in the automatic changer.
It is, therefore, an object of the present invention to provide an automatic changer in which it is possible to accommodate a large number of cartridges, with excellent space efficiency, without increasing the size of a hand mechanism section, even when a CCD that requires the mounting of a condenser lens is mounted on the hand mechanism section in order to read identifiers printed on labels adhered to cartridges that accommodate recording media.
In order to achieve the above object, according to one aspect of the present invention, there is provided an automatic changer comprising a cartridge accommodating section that accommodates a plurality of cartridges such that these cartridges can be selected, and an accessor that selects one cartridge from the accommodating section, and conveys the selected cartridge to a predetermined position within a casing, the automatic changer being structured to read an identifier of a label adhered to at least one surface of a cartridge, and identifies each cartridge, wherein a hand mechanism that holds a cartridge and pulls the cartridge into the internal space or releases the cartridge from the internal space, is provided within an internal space that accommodates the cartridges; an identifier-image pick-up member is disposed in the inner part of the internal space; a condenser lens is disposed on an optical axis of the image pick-up member in a move direction of the hand mechanism; and the hand mechanism in a status of not holding the cartridge is moved within the internal space thereby to focus the identifier on the image pick-up member.
Further, according to another aspect of the invention, the image pick-up member may be a CCD. Further, a cartridge may be a magnetic-tape cartridge, a cartridge that accommodates an optical magnetic disk, or a cartridge that accommodates a non-volatile IC memory.
Further, according to still another aspect of the invention, in general, it is possible to use a bar code for the identifier. It is also possible to use a mark other than a bar code for the identifier.
Further, according to still another aspect of the invention, there is provided an automatic changer in which the accessor is structured to be able to move along a guide rail provided on a floor surface of the casing in a width direction; cartridge accommodating sections are provided at both sides of the accessor along a moving direction of the accessor; and a rotation mechanism is provided that can convey a cartridge to any one of the cartridge accommodating sections based on a rotation of the accessor in a horizontal direction.
Further, according to still another aspect of the invention, there is provided the automatic changer of the above aspect wherein a driver, as a recording/reproducing apparatus to which the accessor conveys a cartridge, is provided at one side of the accessor in its moving direction. Further, according to still another aspect of the invention, there is provided the automatic changer of the above aspect wherein the cartridge accommodating section at one side at which the driver is provided is fixed, and the other cartridge accommodating section at the other side is formed as a magazine that can be exchanged. Further, according to still another aspect of the invention, there is provided the automatic changer of the above aspect wherein the magazine that can be exchanged is detachably fitted to an open/close window of the automatic changer. Further, according to still another aspect of the invention, there is provided the automatic changer of the above aspect wherein a ball screw applied in a width direction of the casing is engaged with the other end of the guide rail of the accessor, and the accessor moves based on a rotation of the ball screw.
According to the automatic changer of the present invention, the image pick-up member that reads an identifier attached to a cartridge and recognizes this cartridge and the condenser lens are provided within the casing and the hand mechanism of the accessor respectively. Therefore, the image pick-up member and the condenser lens do not stretch out from the accessor, and it becomes possible to make the accessor compact. As a result, it is possible to reduce the sizes of the automatic changer and increase the number of cartridges accommodated within the automatic changer, without changing the sizes of the automatic changer.